Extreme weather and water

Extreme weather and water

From the recent record-breaking heat wave in Australia to the devastation of Hurricane Sandy in the US, extreme weather events are increasingly common. Impeller spoke with Michael D. Lemonick, co-author of Global Weirdness to discuss how climate change is affecting the weather and the world’s water, and what we can learn from the anti-smoking campaign. He is also a senior science writer at Climate Central.

Why did Climate Central produce Global Weirdness? What does it do differently than other books on climate change?

What made us produce this book was actually a column in the New York Times by Thomas Friedman where he basically wrote that he was tired of all the arguing back and forth about climate change. He thought that all the experts on climate change should sit down and write what we know about climate change, and how we know it, so that a child could understand it. A publisher read that column and found Climate Central, and thought that we would be the ideal organization to produce the book since that is really our mission, to provide information without advocacy, purely based on the science.

So what is weird about the weather? Why is the word “weird” used in the title?

There’s a debate in the climate community about what to call the phenomenon – people have talked about “the greenhouse effect,” but in the 1990s settled on “global warming,” since the world is warming up. But that is just the first thing that has happened as a result of greenhouse gases. Sea levels are rising, glaciers are melting, there are more droughts and heat waves and torrential rainstorms, and spring is coming earlier in many parts of the world. “Global warming” doesn’t capture the full range of what is going on. Since the weather is getting strange to us, “global weirdness” is a better way to capture essentially the strangeness of what is going on.

What is the time frame when it comes to climate change – is a drastic shift in the weather expected, or will this be something that happens over a hundred years?

There’s no magic line we will cross and suddenly things will change dramatically. What people will see is that weather that we used to see rarely, we will start to see more often. So the very severe drought that affected the US this year, we haven’t seen anything like this since the 1950s. It is likely that as the world warms, we will see the next drought sooner, and more often year after year. Europe had a cold winter in 2012, and the US had a very warm winter. Both cases are unusual, but as long as we keep putting CO2 into the atmosphere, changes will simply continue.

How much can the oceans be expected to rise, and when? How much have they already risen?

Up until now, since about 1900 the oceans have gone up around eight inches (20 cm), on average worldwide, though what has happened locally depends on other factors as well. In Scandinavia, the land is still rising after the last glacial period 20,000 years ago, so the sea level is trying to catch up with rising land. In other places land is falling, such as in the US along the Gulf Coast where people are pumping so much oil and gas from underground that the land is actually deflating and sinking, so the effect is magnified there. The best projections we have to date is that we’ll see an additional three feet (91 cm) of rising levels by 2100, and as time goes on the increase will be even greater.

What is the danger in rising sea levels?

The danger has to do with the fact that many, many big cities and concentrations of populations are on the seaside and trillions of dollars of infrastructure have been built there. As the sea levels rise, combined with surges of water from storms that push water ashore, it will be increasingly difficult to protect these cities from flooding and more expensive to move inland since there is so much invested on the shore. And for countries that don’t have a huge infrastructure, like Bangladesh, 100 of millions of people will be without a lot of protection from flooding. Also, as sea levels rise freshwater supplies can become contaminated. In Miami, the sea is pushing underground into freshwater supplies so people now have to dig new wells further from the ocean.

How are cities handling the effects of climate change?

Cities are waking up and taking this quite seriously. For example, there is an organization based in The Netherlands called the Delta Alliance, which is a group of major cities on river deltas that are sharing expertise to protect themselves from flooding. If the world can’t come together and limit emissions, cities will have to revert to Plan B and adapt to climate change. They can’t afford to see if emissions will drop, since the effects are here and will just get worse. Ideally we would limit emissions so we wouldn’t have to do these things, but no responsible city official is going to wait and see.

How does climate change affect drinking water supplies?

Not in a good way. I already spoke about the intrusions of salt water into freshwater on coasts, but other things are happening. In areas where droughts become more intense, people will have to drill down to take water from underground aquifers, which puts pressure on the water supply, particularly when people draw water faster than it can be replenished. Also the weather that feeds mountain glaciers will be diminished. Since these glaciers are the source of major rivers in India and south Asia, they will be releasing less freshwater and earlier in the summer, resulting in water shortages later in the summer.

What is the number one thing that needs to be done to stop climate change?

We need to limit our emissions of greenhouse gases. It is the primary cause and the primary solution. The book doesn’t make any recommendation about how to do that. We are a non-advocacy organization, so we don’t endorse any particular actions – we try to remain neutral. The book talks about the advantages and disadvantages of all possible solutions. Though the ability to take significant action on climate change is limited by people’s willingness.

When it eventually came out in the 1960s that smoking could cause lung cancer, even though it was a scientific fact most people would not accept several restrictions about where and when they could smoke. Today things have changed dramatically – we are not surprised anymore by smoking regulations because society has collectively decided that smoking is socially unacceptable behavior. If through education we can make emitting carbon socially unacceptable, the way smoking is, then governments could pass laws restricting emissions and people would say that it is kind of annoying but the right thing to do.

Photo: Australia’s Bureau of Meteorology

by Chad Henderson